Cylinder lock



Oct. 28, 1958 l.. J. BlRo 2,857,753

' CYLINDER LOCK Filed May 24, 1954 4 Sheets-Sheet 1 Eff Irl-.2

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CYLINDER Locx l Filed may 24. 1954 A 4 sheets-sheet 2 L. J. BIRCCYLINDER LOCK Oct. 28, 1958 4 Sheets-Sheet 3 Filed May 24. 1954 4Sheets-Sheet 4 IIN-l.

INVEN'roR/ LADISLAO JOSE. BIRO A-r Ton NSY United States Patent()CYLINDER LOCK Ladislao J. Biro, Buenos Aires, Argentina Application May24, 1954, Serial No. 432,002

13 Claims. (Cl. 70-421) The present invention refers to a drum lock andmore particularly to an automatic prevention ratchet, which, by themanner in which it acts as an opposing obstacle in the key drum, acts asa guarantee for preventing any violation or illicit maneuvering of thelock.

As is known, combination locks, consisting of one operating cylinderfastened by tumblers, are apparently inviolable as the pin tumblers ofthe combination being several, and the secret thereof not being known,it is very diicult to effect the displacement degree required (for eachof them) for the loosening ofall the parts which form the set; but sinceit is not by means of the key that delinquents attempt to suppress theobstacle represented by the seal, the security is therefore relative, assame may be vanquished by anyone knowing the easy process which evilgenius has created in order to open the lock without a key.

In effect, since the cylinder has an indispensable rotating play so thatthe pin tumblers may coincide in the perforations of each part, anyperson may liberate said cylinder if, with patience, he employs aninstrument in order to obtain a fractional rotation in said drum, whilstwith another instrument same is inserted in the key channel in order tolift, one by one, the pin tumblers of the combination. In this operationeach pin tumbler must be mounted and retained in the respective edge ofthe perforation of the drum, which means that, with the secondinstrument, the alignment thereof may be obtained, as if done by a key,in order to stop the fastening of the lock which will allow the drum torotate. This can easily be accomplished by means of the use of the firstinstrument.

It is interesting to note the manner wherein the present inventionsolves the old and important problem of the cylinder locks, for, sincethe cause of the vulnerability of the lock is precisely the freedom ofplay in the cylinder, this is overcome by immobilizing a catch, actingas an obstacle of access into the key channel, so that if any other thanthe proper key is introduced said catch will be moved out of place andwill hinder the movement required for the operation of aligning thecombination pin tumblers.

This means that the intruder, although he may know the manner in whichto open the lock without a key, will be unable to do so in this case, asthe latching element acts precisely as a blocking means in the keychannel giving access to the pin tumblers of the combination.Consequently any movement tending to force a passage towards said pintumblers will be sucient to produce a blocking thereof, so that it wouldbe futile to try and align the pin tumblers, and they will remain in theline corresponding to the union between the cylinder and the xed bodythereby preventing rotation of the cylinder. The cylinder, apart fromthe pin tumblers of the combination possesses one or more latches which,with the tension caused by a spring is or are interposed in the channel,so as to block the entrance of illegal instruments. Said latch coincideswith a groove which in turn r"ice coincides with a section able toreceive said latch but with axial play movement of said pin tumblers, intheir corresponding perforations so that anyone attempting to operatesame in an illicit manner will cause the latch, or latches, to enter theperforation of the xed body, in which case the necessary rotatingfraction of the drum cannot be obtained, thus serving as a retainer ofthe pin tumblers.

Apart from what has been stated, several are the objects pursued by thepresent invention, amongst which may be stated that of manufacturing acylinder lock which can offer a real guarantee insofar as illegal usesare concerned.

Another object is that of establishing a blocking means with thelatches, which, although they can be displaced to give entrance to thecorresponding key, must return to their normal position, in view of thefact that these latches are converted into blocking means, as soon asthe least displacement occurs.

Another object is to oder absolute security for this type of lock,universally known, as -most manufacturers maintain special researchservice, with the object of solving any problem created by the failureof aligning the pin tumblers with the help of a fractional rotation ofthe cylinder in order to ensure their positions.

Another object of the invention is that of offering a simple basis forthe application of the security device, as it only comprises latcheswhich, by their disposition, do not alter to any extent, theconstruction and manufacture of locks.

Another object is that of obtaining in the security device a totallyautomatic effect which does not offer any complications to the user, asthe key is the instrument which displaces the latch -and normalizes itsposition once it has been inserted into the key channel.

Another object is that of increasing the security of the lock, asdisposing the latch or latches in different relative positions in thekey channel, it is possible to form a secret code in order to preventillegal usage.

The further objects of this invention will be shown throughout thefollowing description, which for greater clearness and comprehension hasbeen illustrated with several drawings in which are represented theimproved lock in one of its preferred forms of realization, thus:

Fig. 1 is a longitudinal section, through the lock of the presentinvention, and represents the position of the parts before introducingthe key.

Fig. 2 i-s a transversal section of the line 2-2 of Fig. l.

Fig. 3 is a similar view of Fig. 1 but showing this key partiallyintroduced.

Fig. 4 is' a similar view of Figs. 1 and 3 but also showing the keyintroduced in a furthe-r degree within the lock.

Fig. 5 is a ltransversal section of the line 5-5 of Fig. 4.

Fig. 6 is a longitudinal section of the lock, showing the position ofthe partswith the key wholly introduced.

Fig. 7 is a tranversal section of line 7-7 of Fig. 6.

Fig. 8 is a view of the body of the key for opening the lock.

Fig. 9 is a section of line 9-9 of Fig. 8.

Fig. l0 is a key of different execution, which, instead of one, has twoindentations destined for locks with two latches in diiferent planes.

Fig. 11 is a transversal section of the lock with two Fig. 13 is alongitudinal section of the lock corresponding to the example of Figs.11 and 12. In this cut is shown the manner in which the key penetrates,separating the latches, which are to occupy their normal place in theirrespective indentations when the key is totally introduced.

Fig. 14 is a transversal section of the lock in a different execution inwhich the latches are set Von the same lineiriV antagonistic opposition.

Fig. 15 is a part of the key destined to the type of lock with twoantagonistic latches, as in Fig. 14. This key has been cutlongitudinally so as to show its extreme end shaped in V and the wedgewhich forms the double bevel of the indentation, also shaped in V.

Fig. 16 is a longitudinal section through the lock of the presentinvention and is directed to a modification wherein two tumblers have agreater movement play than the remaining tumblers.

In the different drawings the same reference numbers indicate equal orcorresponding parts, the elements being indicated by letters.

As may be seen in the drawings, the lock comprises a fixed body apossessing a longitudinal cylindrical hollow 1. In said hollow isrotatively included a drum b having a key channel 2 for access throughits mouth 3 for introducing key c.

Said fixed body a has a plurality of guide chambers 4, 5, 6, and 7 whichinclude several pin tumblers 8, 9, 10 and 11, which form the closingcombination.

Pin tumbler 11, the remotest from the mouth 3, is of a smaller diameterthan the other pin tumblers, so that in its chamber 7, pin tumbler 11has a movement play greater than that of pin tumblers 8, 9, and 10; allthe pin tumblers are pressed by springs 12, so that thus tensioned theypenetrate perforations 13, 14., 15 and 16; said perforations, made inthe drum from the periphery of same up to the key channel 2, serve asguides to the coacting tumblers 17, 18, 19 and 20. In perforation 16,said pin tumbler 11 also has a lateral movement play greater than thatof the pin tumblers 8, 9, and 10 in their perforations 13, 14 and 15;with this movement play in perforation 16 and in guide chamber 7, pintumbler 11, in spite of passing between the fixed body and the drum,allows a fractional rotative movement to said drum b, but this movementis impeded by the other pin tumblers.

The coacting tumblers 17, 18, 19 and 20 are projected into key channel 2as a consequence of the pressure of springs 12. With the pressure ofsprings 12 the pin tumblers and coacting tumblers occupy the position ofFig. 1 which is the closing position, as the pin tumblers 8, 9, 10 and11 lie athwart the fixed body a and the drum b As drum b must rotate inorder to displace a latch bolt by means of wing 21, key c must set thepin tumblers and the coacting tumblers so that the union of each pinturnbler with its respective coacting tumbler coincides with the line22-22 shown in Figs. 1, 3, 6 and 13.

To this end, key c possesses a plurality of crests 23 with a projectionproportioned to the run which must be made by the coacting tumblers andpin tumblers, so that their respective unions may coincide with line22-22. Thus, when the key is totally introduced, as shown in Fig. 6, thecrests 23 elevate the coacting tumblers in order that the pin tumblersmay be free of drum b and remain with their extreme ends level with line22-22. In this state, that is to say, with the key inserted (Fig. 6)there is no inconvenience for the key to rotate the drum so that, withits wing 21, it provokes the displacement of the latch proper of thelock.

After said operation, when withdrawing key c, the springs 12 force thecoacting tumblers to return to their original position in which the pintumblers lie across the junction of the fixed body a and the drum b.

Any lock with pin tumbler combination is liable to be violated byemploying an instrument for raising the coacting tumblers and pintumblers, aligning them on the periphery of the drum, so that the pintumblers' may rest on the borde-r of the perforations of said drum; theretaining of the pin tumblers in the border of their perforations ispossible owing to the movement or play of the pin tumblers in theirguide chambers and perforations, which allows for the drum to besufficiently rotated so that, when the pin tumblers are raised, they maybe retained in the edge offered by the rotation.

That is why, in the new lock, in order to render it inviolable, drum bis provided with at least, one latch d which forms a blocking to theaccess of any instrument in the 4rear part of channel 2, and if it iswithdrawn, said latch produces the immobility of drum b.

To this end, latch d is disposed in a respective guide 24 which passesfrom the periphery of drum b up to the key channel 2. In the inoperativeposition of drum b, guide 24 coincides with groove 25, which is made inthe fixed body a; the latch d being of a greater length than that ofguide 24, has its outer extreme 26 ush with the periphery of drum b,whilst its inner extreme 27 is projected in the key channel 2 as anobstacle to a rear access in said channel; said latch is pressed byspring 2S towards an inoperative position in which the extreme 26remains precisely ush with the periphery of drum b in such a manner thatif an instrument is inserted in channel 2, upon displacement of latch d,so that the instrument may pass, the extreme 26 fits into grooves 25.

The movement of play of extreme 26 of the latch in the groove 25 issmaller than the movement play of the pin tumbler 11 in its guidechamber 7 and perforation 16, so that when latch d is displaced towardsthe operative position (Fig. 5) the fixing of the latch d in the groove25 annuls the movement of drum b; that is to say that the possiblefraction of movement of drum b allowed by the movement play of pintumbler 11, is annulled by the blocking imposed by latch d enteringgroove 25.

In this manner it is not worth while trying to raise the coactingtumblers 17, 18, 19 and 20 with unlawful instruments, for, as drum b isunable to rotate, and pin tumbler 11 cannot reach the border ofperforation 16; this means that even repeating the operation of raisingthe coacting tumblers, the pin tumbler 11 falls again without findingany Iretaining means, so that it maintains a blocking position for drumb.

The fact that pin tumbler 11 has a greater movement play with respect topin tumblers 8, 9 and 10, establishes another combined security, for aspin tumbler 11 is the most remote from mouth 3, the intruder mustforcibly displace the coacting tumblers 17, 18, and 19 in order to reachcoacting tumbler 20 with the instrument. And if he commences bydisplacing the coacting tumblers 17, 18 and 19, the lesser movement playof their respective pin tumblers 8, 9 and 10 will prevent drum b frombeing rotated in order to reach pin tumbler 11 and raise it to theborder of perforation 16.

Therefore, since latch d with its extreme 27 and wing 29 totally coversthe part of the channel 2 opposite to that part covered by the coactingtumblers, it is difficult if not impossible to operate with instrumentsdifferent to that of the key. This is because introduction of an illegalinstrument into the part of channel 2 covered by latch d displaces latchd immobilizing the drum by the entering of the extreme 26 in groove 25,and if the intruder, so as not to move the latch, acts in a differentmanner with the instrument through the coacting tumblers 17, 18 and 19,as has been mentioned, pin tumbler 11 cannot be jammed, because pintumblers 8, 9 and 10 prevent it due to the lesser movement play.

The latch d is disposed near the coacting tumblers 1S and 19 in such amanner that it forms a closing curtain opposite to coacting tumbler 19;in this case the intruder is obliged to raise such coacting tumbler 19in order to reach coacting tumbler 20; in which case, pin tumbler S 10,Adue to its lesser tolerance play annuls the movement of the drum,preventing pin tumbler 11 from being raised to the edge of perforation16.

All this is no obstacle for key c for it has vmeans for acting correctlywithout altering the position of latch d when totally inserted, as inFig. 6. In effect, this key has an opening 30 which coincides preciselywith the place in which is found latch d, and as may be appreciated,said key c is bevelled in its extreme 31 so that when inserted it mayact as a wedge with said bevelled extreme 31. The inner extreme 27 oflatch d is sharpened, so that when key c is inserted, with the wedgeformed by its bevel 31, it easily separates latch d as graphically shownin Fig. 5. Latch d is displaced, entering its outer extreme 26 in groove25. When key c reaches the total insertion position (Figs. 6 and 7)latch d pressed by spring 28 recovers its normal inoperative position,as said latch is projected through opening 30 presented in coincidence.In this manner, latch d emerging from `groove 25 does not hinder themovement of drum b which, being also free of the closing operation ofpin tumblers 8, 9, 10 and 11 can be rotated by means of the key, inorder to effect the displacement of the latch bolt in the opening orclosing sense. The opening 30 is also bevelled at 32, so that whenwithdrawing the key from the lock, said bevel 32 displaces latch d inorder to allow the withdrawal of the part of the key which is behindsame.

If desired, for additional security one of the pin tumblers on the sideof the lock toward the mouth of the lock may also be provided withgreater movement play in its guide chamber in the same manner as pintumbler 11. This is the modification as shown in Fig. 16 wherein 4', 5',6', and 7' are guide chambers corresponding to chambers 4, 5, 6, and 7of Fig. l. Pin tumblers 8', 9', 10', and 11' correspond to pin tumblers8, 9, 10, and 11 of Fig. 1, and coacting tumblers 17', 18', 19', and 20'correspond to the respective coacting tumblers of Fig. 1. Perforations13', 14', 15', and 16' correspond to the respective perforations of Fig.l. Latch d corresponds to latch d of Fig. l. In this modification pintumbler 8' as well as pin tumbler 11 are of smaller diameters than theremaining pin tumblers so that each of said pin tumblers 8 and 11 havegreater movement play in their respective guide chambers than that ofpin tumblers 9 and 10'.

In case of having two latches a as shown in Fig. 14, both latches beingbi-symmetrical are urged by their respective springs 2S actingantagonistically and abutting in the line in the middle of channel 2',that is, the inner extremes 27 abut against each other whilst therespective outer extremes 26 remain ush with the periphery of drum b.

In this case the extremes 27 and wings 29 act together forming a curtainwhich covers the part which is not reached by the coacting tumblers 17,18, 19 and 20.

Thus even when an illegal instrument is introduced, it is diicult if notimpossible to violate the lock as the channel is obstructed by thepresence of extremes 27 and wings 29, for, although this instrument mayseparate the latches d these render impossible the required turning ofdrum b due to the lesser lateral movement play that eX- tremes 26 havein grooves 25 with respect to the movement play of pin tumbler 11 in itsguide chamber 7; and

model in Fig. 14 must have a double sharp edge 31, that' is to say thatsaid key c" must be bevelled in V as shown in Fig. 15. In this manner'the key forms a wedge with the joint of both latches d, in such amanner that it is easily inserted. The opening 30 must also possess twobevellings forming a wedge in V as shown in Fig. l5.

In the example of Figs. 1l, l2 and 13 the lock also has two latches d;but in this case the latches are placed in different planes andpositions. For example, the inferior latch is set in identicalconditions as the latch of Figs. l to 7, but the superior latch is setnearer to the mouth 3 and in a place in which its extreme 27 with itswing 29 covers the rest of the key channel corresponding to that i partof the channel covered by the coacting tumblers 17, 18, 19 and 20.

This means that between the two latches d (Fig. 1l) the access to therear part of channel 2 is completely closed, and as both latches, intheir normal inoperative position, have their extremes 26 flush with theperiphery of drum b, any displacement of said latches in order topretend to introduce an instrument, produces the setting of saidextremes 26 in the corresponding groove 25 which prevents the rotatingmovement of drum b. As the movement play of extreme 26 in groove 25 issmaller 4than the movement play of at least one of the pin tumblers tobe found behind the latches, it is impossible for the furthermost pintumbler to mount the edges of their corresponding perforations 15 and16.

Key c' as shown in Figs. l0 and 13, possesses two openings 30, one foreach latch d, correspondingly, so that in inserting the key as shown inFigs. l2 and 13, once it has been totally inserted, said openings allowthe resetting of both latches d to their inoperative position, Fig. ll.Key c' with its crests 23 acting against thecoacting tumblers, levelsthe pin tumblers as at line 22-22 so that, out of the drum, said pintumblers may not impede the rotation of same for the opening or closingoperation of the lock. The key c', in the event that the tip of the keyis high enough to reach the upper latch, has a double bevel at 31 todisplace each latch. Otherwise, an appropriate bevel is provided at theforwardmost edge of the key at the point where the key is high enough todisplace the upper latch.

This application is a continuation-in-part of copending applicationSerial No. 393,883, liled November 23, 1953, now abandoned.

It is obvious that in carrying out this invention, modifications ofdetail and structure may be introduced without this implying a departurefrom the scope of said invention, the characteristics of which areclearly defined in the following claims.

I claim:

l. A tumbler lock comprising a fixed body defining a longitudinalcylindrical hollow, a revolvable drum enclosed within said hollow, saidxed body having a plurality of guide chambers communicating with saidhollow,

v said drum having a plurality of perforations in alignment if saidinstrument is directed through the part covered l by the coactingtumblers 17, 18, 19 and 20, because pin tumbler 10 has a lesser movementplay than pin tumbler 11, the raising of the coacting tumbler 19 withpin tumbler 10 will not allow the movement of drum b so that pin tumblerllmay reach the edge of perforation 16 since the drum is still preventedfrom rotating suiciently because of the latches. This means that it isimpossible to elevate said pin tumbler 11 as it cannot reach the edge inview of the blocking imposed by pin tumbler 10.

The key proper for acting in the lock, according to with said guidechambers when said drum is in its inoperative position, pin tumblersmounted within said guide chambers, said pin tumblers being urged towardsaid perforations, tumblers in said perforations coacting with the pintumblers in said guide chambers, a key channel in said drum, saidcoacting tumblers normally projecting from said perforations into saidkey channel, a guide channel in said drum extending from the peripheryof said drum to said key channel, a groove in said xed body, said groovebeing in alignment with said guide channel in the inoperative positionof the drum, at least one latch having a length greater than said guidechannel, said latch being positioned within said guide channel and urgedtoward an inoperative position within said drum in which the outerextremity of said latch is flush with the periphery of the drum whilethe inner extremity of said latch projects into said key channel to actas an obstacle l to access to the rear of said key channel, at least oneof said pin tumblers being mounted to the rear of said latch and atleast one of said pin tumblers mounted to the rear of said latch havinga lateral play movement in its guide chamber which is greater than thelateral play movement of said latch and at least one of the pin tumblerspositioned forwardly of said rear pin tumbler in their respective guidechannel and guide chamber, so that said rearpin tumbler having saidgreater lateral play movement cannot be lifted without the use of theappropriate key since suiiicient rotation of said revolvable drum toenable said rear pin tumbler to be caught on the peripheral edge of saidperforations is prevented by said latch or by one of said forward pintumblers.

2. A tumbler lock as recited in claim l in which said pin tumblers arespring-urged toward said perforations and said latch is spring-urgedtoward said inoperative position within said drum.

3. A tumbler lock as recited in claim 1 in which said tumblers obstructthe upper portion of said key channel and said latch obstructs theremainder of said key channel.

4. A tumbler lock as recited in claim 3 in which the inner extremity ofsaid latch is formed with a key obstructing the portion of said keychannel opposed to the portion of said key channel obstructed by saidcoacting tumblers.

5. A tumbler lock as recited in claim 1 in which said latch ispositioned between adjacent tumblers.

6. A tumbler lock as recited in claim 1 in which said latch and atumbler immediately adjacent thereto each possess a lateral playmovement in their respective guide channel and guide chamber which issmaller than the lateral play movement of said pin tumbler mounted tothe rear of said latch.

7. A tumbler lock as recited in claim l in which the rearmost pintumbler has a lateral play movement in its guide chamber which isgreater than the lateral play movement of said latch and all of theremaining pin tumblers in their respective guides.

8. A tumbler lock as recited in claim 1 in which a plurality of latchesare provided each of said latches being positioned within a separateguide channel, each of said 'guide channels being positioned in adiierent plane,

said latches being urged toward an inoperative position within saiddrum.

9. A tumbler lock as recited in claim 8 in which said guide channelsenter said key channel from opposite sides` 10. A tumbler lock asrecited in claim l in which a plurality of latches are provided each ofsaid latches being positioned within a separate guide channel, at leasttwo of said guide channels being positioned in the same plane and inwhich said two guide channels enter said key channel from oppositesides.

11. A pick-resistant tumbler lock comprising a fixed body provided witha longitudinal cylindrical hollow, a revolvable drum rotatablypositioned in said hollow, a plurality of spaced parallel chambersincluding outermost chambers and intermediate chambers in said iixedbody, a plurality of spaced parallel recesses including outermostrecesses and intermediaterecesses in said drum, a key channel in saiddrum, said recesses extending between said key channel and the peripheryof said drum and being positioned for movement into and out of registrywith said chambers upon rotation of said drum, spring-pressed pinsmounted for sliding movement in said chambers and said recesses and eachincluding a driver and a tumbler, a guide channel in said drum, saidguide channel extending between the periphery of said drum and a lowerside of said key channel, a groove in said fixed body, said groovecommunicating with said guide channel when said chambers and saidrecesses are in registry, a latch slidably mounted in said guide channelfor movement into and out of said key channel, said latch entering saidgroove to prevent rotation of said drum when said latch is moved out ofsaid key channel, resilient means urging said latch out of said grooveand into said key channel, the pins in said outermost chambers andrecesses having a `greater play in their chambers and recesses than thepins in said intermediate chambers and recesses and the latch in itsgroove, the inner end of said latch having a downwardly projectingportion completely closing the lower portion of said key channel whensaid latch is out of said groove.

12. A pick-resistant tumbler lock as recited in claim ll in which saidgroove and said guide channel are positioned between said outermostpins.

13. A pick-resistant tumbler lock as recited in claim 11 in which saidgroove and said guide channel are positioned between said intermediatepins.

References Cited in the le of this patent UNITED STATES PATENTS 758,024Taylor Apr. 19, 1904 758,026 Taylor Apr. 19, 1904 758,027 Taylor Apr.19, 1904 2,022,070 Williams et a1 Nov. 26, 1935 2,064,955 singer et a1Dec. 22, 1936 FOREIGN PATENTS 73,832 Denmark Feb. 11, 1952

